Pumping apparatus for an internal combustion engine

ABSTRACT

An apparatus ( 10 ) for pumping lubricant in an internal combustion engine, includes a lubrication pump ( 11 ) for the lubricant, and electric motor means ( 12 ) for driving the pump ( 11 ), the lubricant being contained in reservoir(s) in which at least the lubrication pump ( 11 ) is immersed, and the motor means ( 12 ) including a stator ( 14 ) and rotatable motive member ( 15 ) the stator ( 14 ) and rotatable motive member ( 15 ) being in contact with the lubricant from the reservoir(s).

DESCRIPTION OF INVENTION

This application claims priority under 35 U.S.C §365(c) to internationalpatent application PCT/GB99/03350 filed Oct. 8, 1999, which in turnclaims priority to United Kingdom patent application 9822152.6 filedOct. 12, 1998 and United Kingdom patent application 9913584.0 filed Jun.14, 1999, the entire disclosures of which are incorporated herein byreference.

This invention relates to a pumping apparatus and more particularly to apumping apparatus for pumping lubricant in an internal combustionengine, and to a sump and an engine incorporating such a pumpingapparatus.

In an internal combustion engine it is common practice to provide alubricant pump which is operative to pump lubricant, usually oil, toparts of the engine which require lubrication. The oil drains back to asump under gravity.

Known such pumps are driven by a mechanical coupling with a driven partof the engine, such as from a gear or cam carried by e.g. the camshaftor crankshaft of the engine. Thus the choice of positions at which theoil pump must be sited, is restricted by the nature of the mechanicalcoupling. The pump is only driven when the driven part of the enginemoves, i.e. when the engine is running.

As a result, during start-up of an engine particularly from cold, thereis a short period before an adequate supply of oil is delivered to theengine parts which require lubrication. Thus during start-up, the engineis particularly prone to wear.

Also in modern engines which incorporate parts which rotate at highspeed, such as the rotor of a turbocharger, such rotating parts tend tocontinue to rotate for some time after the engine is switched off andthe driven part of the engine from which the oil pump is driven, stopsmoving. Thus such rotating parts tend to be inadequately lubricated whenthe engine is switched off and wear is aggravated as such rotationresults in a temperature rise due to the cessation of force fedlubrication, which acts as a heat transfer means.

Another problem with conventional oil pumps is the necessity to providepipework for a supply of oil to and delivery of oil from the oil pump,which can be complicated by the position at which the oil pump ismounted being governed by the mechanical coupling to the driven part ofthe engine.

Yet another problem with conventional oil pumps which are driven by adriven part of the engine is the inability to control the speed of thepump other than as a result of engine speed. Particularly, as enginespeed increases, so will the oil flow delivered by the pump. At highengine speeds, it would be preferable to limit the oil pump speed forthe most efficient lubrication of the engine, and to limit wear on theoil pump itself.

It is well known to drive a pump using an electric motor but this hasnot been adopted generally in an engine environment for several reasons.First, there are the economic considerations of providing a motor drivenpump. Second, a motor would generate heat and would itself requirecooling.

According to a first aspect of the invention we provide an apparatus forpumping lubricant in an internal combustion engine, the apparatusincluding a lubrication pump for pumping the lubricant, and electricmotor means for driving the pump, the lubricant being pumped from areservoir in which at least the lubrication pump is immersed, andcharacterised in that the motor includes a stator and a rotatable motivemember, the stator and rotatable motive member of the motor means beingin contact with lubricant from the reservoir.

Thus the temperature of the motor may be stabilised by the lubricant incontact with it, and furthermore, the motive member and/or bearingscarrying the motive member may readily be lubricated. Because the pumpis driven by a motor and not a mechanical coupling from a driven part ofthe engine or other machine, there is less restriction on thepositioning of the pump compared with conventional arrangements.

Thus the potential technical problems of using a motor driven pump e.g.for pumping lubricant in an internal combustion engine or other machine,may be overcome. Even though a motor driven pump may be more expensivethan a conventional pump driven e.g. from a driven part of the engine,the benefits achieved may offset this extra cost.

Amongst the advantages of providing a pumping apparatus in accordancewith the invention in such an environment arc that the speed of the pumpmay be controlled because the pump is not mechanically coupled to adriven part of the engine; the pump may be actuated independently of theengine and thus may pump lubricant prior to start-up and subsequent toswitching off the engine so that the engine is less prone to wear duringsuch periods; the performance of the motor/pump may be used as adiagnostic tool for diagnosing a) engine malfunctions such as forexample a blockage in a lubrication passageway, and b) engine wear whichtends to result in an increased requirement for lubricant to be pumped.

Preferably the reservoir in which at least the lubricant pump isimmersed, is a sump of the engine from which lubricant is pumped tomoving parts of the engine.

In one embodiment, the pump and the motor means are arranged with thepump and the motor means immersed in lubricant in the reservoir. Thusthe motor need not have a housing or other outer casing. In anotherembodiment where the pump only is immersed in the lubricant, the motormeans may include a motor housing with one or more passages for thelubricant e.g. from the pump, to the interior of the motor housing. Ineach case by virtue of the pump and/or pump and motor means beingimmersed in the fluid in the sump, the temperature of the motor meansand the pump will be stabilised by the fluid and will realise thetemperature of the lubricant.

By providing a pump or pump and motor means which are positioned in thesump, there is no need to provide pipework to the pump for the fluid tobe pumped. Preferably, the pump is connected to a remote filter whichfilters the fluid e.g. prior to the lubricant being directed to movingparts of the engine.

In a preferred arrangement, the fluid to be pumped may be pumped by thepump through a heat exchanger where the lubricant is cooled by a coolantin thermal contact therewith. The coolant may be for example only, wateror another coolant which may be predominantly water or the like.

Preferably the heat exchanger is located closely adjacent to a housingof the pump exteriorly of the reservoir, e.g. in the air, so that theair may perform some cooling of the fluid. Where the pump pumps fluidfrom the sump to a filter, a fluid outlet from the heat exchanger may beconnected directly to a housing in which the filter is provided or thefilter housing may be integral with the or a housing of the apparatus.

The motor is preferably an electric motor in which case there may beprovided a control means for the motor. The control means may be of anelectronic nature, the temperature of which may need to be retainedbelow a threshold level. Most conveniently the control means ispositioned at least adjacent the pump so that there is no need for thereto be long leads between the control means and the motor. Where there isprovided a heat exchanger through which a coolant flows to cool thefluid to be pumped, the control means may too be cooled by the coolant.For example the control means may be contained in a housing in thermalcontact with the heat exchanger.

The control means may be adapted operatively to be connected to amanagement system controlling an engine or other machine in which thefluid is to be pumped.

In another embodiment the motor is an electric motor having externalstator windings and an internal rotor, the internal rotor includes anaxially extending opening with generally radially inwardly formationssuch as gear-like teeth, and the pump includes an impeller which isreceived in the axially extending opening, the impeller having generallyradially outwardly extending formations such as gear-like teeth, whichco-operate with the radially inwardly extending formations of the rotorso that the impeller is driven as the rotor rotates, the radiallyoutwardly extending formations of the impeller pumping the fluid as theimpeller is rotated.

Thus the impeller and motor may be integrated substantially to reducethe axial extent of the apparatus compared with an apparatus in which animpeller is connected at an axial end of a motor rotor or otherrotatable motive member of the motor. Thus a more efficient design maybe achieved with inherent reductions in manufacturing cost and time. Theoverall size and mass of the apparatus may be lower than that of acomparable apparatus with non-integrated motor and pump elements.

In a preferred arrangement of this alternative embodiment, the impellermay rotate in the axially extending opening of the internal rotor aboutan axis which is parallel to but spaced from an axis about which theinternal rotor rotates whereby in use, at any time, only some of theco-operating formations of the internal rotor and the impeller are inco-operation, and a pumping cavity for fluid to be pumped, is providedbetween the internal rotor and the impeller.

According to a second aspect of the invention we provide an internalcombustion engine having a sump for lubricant to be pumped, and anapparatus according to the first aspect of the invention to pump thelubricant in the engine.

The engine is preferably provided with a management system which mayinterface with a control means of the apparatus, which is operative tocontrol the motor speed, the management system and control meanscontrolling pump speed according to engine operating conditions.

According to a fourth aspect of the invention we provide a method ofoperating an engine of the third aspect of the invention the methodincluding actuating the pumping apparatus prior to start-up of theengine and/or subsequent to switching off of the engine.

According to a fifth aspect of the invention we provide a method ofperforming diagnosis of an engine malfunction including providing to anengine management system, an input from a control means of an electricmotor of pumping apparatus of the first aspect of the invention.

The invention will now be described with reference to the accompanyingdrawings in which:

FIG. 1 is a diagrammatic cross sectional view through a pumpingapparatus in accordance with the invention;

FIG. 2 is an illustrative perspective view of the apparatus of FIG. 1shown in an exploded condition;

FIG. 3 is a view similar to that of FIG. 1 but of an alternativeembodiment of the invention;

FIG. 4 is a view similar to FIG. 2 but of the second embodiment of anapparatus of the invention shown in FIG. 3, and in an assembledcondition.

FIGS. 5a, 5 b, 5 c show alternative ways in which the pumping apparatusof the invention may be mounted with respect to a sump.

FIG. 6 is an exploded illustrative perspective view of a yet anotheralternative embodiment of the invention; and

FIG. 7 is an illustrative end view of the embodiment of FIG. 6.

Referring first to FIGS. 1 and 2 there is shown a pumping apparatus 10for pumping oil or other lubricant in an internal combustion engine.

The apparatus 10 includes a pump 11 which may be a rotor pump, a slidingvane pump, a ring pump or any other pump 11 suitable for pumping theoil. The pump 11 is driven by a motor 12 which in this example is anelectric motor 12 having stator windings 14 and a rotor 15 being amotive means which is connected directly axially to an impeller 16 ofthe pump 11.

The rotor 15 is carried by bearings 17,18 at each end, which bearings17,18 are carried by a motor frame 20, although in this embodiment, themotor 12 has no housing or other casing.

The pump 11 includes a base wall 22 of a housing 23 thereof, the basewall 22 being adapted to be secured in an opening of a sump S of theengine, with a suitable sealing means being provided between the sump Sand the wall 22. Thus the pump 11 and the motor 12 are within the sump Sand in use are immersed in oil in the sump S. Thus the oil is in contactwith the interior parts of the motor 12 particularly with the rotor 15thereof so that the bearings 17,18 are lubricated by the oil, and thewindings 14 are in heat transfer relationship with the oil. Thus thetemperature of the motor 12 and particularly of the windings 14 isstabilised by being in contact with the oil of the sump S.

Typically the oil in a sump of an internal combustion engine will attaina temperature of about 140° C. The motor 12 will of course need to beable to operate in an environment of this temperature. Typically a motormay operate in an environment of up to 200° C.

An internal combustion engine is typically cooled by a coolant such aswater or a coolant which is predominantly water, which is itself cooledby a flow of cooling air through a radiator. The coolant is pumpedaround the engine in a jacket to cool the engine.

In accordance with the invention, there is provided an oil cooler 26through which the oil is pumped by the pump 11 prior to the oil beingdirected to the engine parts where lubrication is required. The oilcooler 26 comprises a heat exchanger 27 in a housing 28, the headexchanger housing 28 being in direct thermal contact with the pumphousing 23. The base wall 22 of the pump housing 23 in this embodimentis a common wall between the pump housing 23 and the heat exchangerhousing 28 such that the heat exchanger housing 28 and the pump housing23 are integrally provided in this embodiment, but could be separatelyprovided and attached as desired.

The heat exchanger 27 has an inlet 29 for oil from the pump 11 and anoutlet 30. In this example the outlet 30 is connected directly to aconduit 31 for the oil to a housing 32 of a filter 33 as shown infigures 5 a, 5 b, and 5 c. These figures show different positions of thesump S at which the pumping apparatus 10 may be provided. The oil outlet30 from the heat exchanger 26 in this example passes through the basewall 22 of the pump housing 23 and heat exchanger housing 28.

Coolant is supplied to a coolant inlet 40 of the heat exchanger 27 andflows in thermal contact with the oil, though the heat exchanger 27 toan outlet 41 from where the oil may pass to the coolant jacket of theengine, or to the radiator of the engine.

The coolant will typically attain a temperature of 90° C. in use andthus the oil passing through the heat exchanger 27 will be cooled.

The speed of the motor 12 is controlled by a control means 45 whichconveniently is electronic in nature, there being leads from the controlmeans 45 to the motor 12 which are not illustrated in the figures. Thecontrol means 45 may be operatively connected via electric leads ortubing, to a pressure sensor (not shown) for example which senses theoil pressure of the pumped oil and may control the motor 12 and thus thepump 11 speed, depending on oil pressure. Alternatively the motor speedmay be controlled as a function of temperature or flow, or a combinationof any of these. There may optionally be an input from an enginemanagement system so that the optimum motor 12 speed can be attained fora given engine speed and oil pressure although in each case, the pump 11speed may be controlled independently of the engine speed i.e. such thatthe pump speed is not wholly dependent on the engine speed as is thecase with a conventional mechanical coupling drive.

It is envisaged that the engine management system may operate such thatthe pump 11 is caused to pump prior to the engine being started suchthat there will be a flow of lubricant to movable parts of the engineprior to such movable parts being driven. For example when an operativeoperates an ignition or other starter switch, there may be a short pausebefore the engine starts while an adequate flow of lubricant is achievedby the pump 11 being operated by a control signal from the enginemanagement system to the control means 45.

Furthermore, in the event of any engine part such as a turbochargerrotor continuing to rotate for some time after the engine is switchedoff, the engine management system may be arranged to signal the controlmeans 45 to continue to operate the pump 11 so as to provide a flow oflubricant to the bearings of such moving part for some time after theengine has been switched off.

This the control means 45 may interface with the engine or other machinemanagement system for optimum performance.

Also, if required, an output from the control means 45 may be used bythe engine management system in fault diagnoses, e.g. to determine oilpassage blockage in the engine.

Because the control means 45 is provided adjacent the heat exchanger 27,and in thermal contact therewith, the electronics of the control means45 will be subject to the cooling effect of the coolant through the heatexchanger 27. Thus the temperature of the electronics of the controlmeans 45 will be stabilised by the heat exchanger 27 and will beprevented from rising above the coolant temperature.

Various modifications may be made without departing from the scope ofthe invention. For example, in another arrangement, the apparatus 10, orat least the component parts thereof which in use lie inside the sump S,may be provided integrally with the sump S rather than being attachedthereto as described, the pump housing 23 base wall 22 being part of awall of the sump S.

In the example described, the pump 11 and the motor 12 are arrangedaxially, but need not be in another arrangement. In the exampledescribed so far, the oil cooler 26 is also arranged generally axiallywith the motor 12 and pump 11, but again need not be.

Referring now to FIGS. 3 and 4, there is shown an alternative pumpingapparatus in accordance with the invention. Similar parts are labelledwith the same reference numerals.

In this alternative embodiment, there is provided an electric motor 12to drive a pump 11, a rotor 15 of the motor 12 being connected directlyto the pump 11 which pump 11 is axially arranged with respect to themotor 12. However, the motor 12 is located exteriorly of the sump S, andaccordingly the motor 12 requires a housing H physically to protect it.The motor housing H is provided integrally with the pump housing 23 inthe arrangement shown, but these could be separately provided andconnected together as desired.

However, the interior of the motor 12 communicates with the interior ofthe pump housing 23 and hence receives oil from the sump S, via a pairof passages P1 and P2 for the fluid. Movement of the motive member(rotor) 15 of the motor 12 will cause some exchange of fluid between thepump housing 23 and the interior of the housing H of the motor 12, butif required, there may be proved an impeller means or the like topromote such oil flow through the motor housing H. In each case, theinterior of the motor 12 and particularly the rotor 15 thereof will becontacted by the oil and thus the bearings 17, 18 which carry the rotor15 will be lubricated by the oil. Also the temperature of the statorwindings 14 will be stabilised by being in thermal contact with the oilof the sump S.

The oil cooler 26 in this example is not arranged axially with respectto the pump 11 or motor 12 but is arranged to one side of the motor 12,and is sealed from the motor 12 and physically separated therefrom by awall W. Oil which is pumped by the pump 11 is fed to the oil cooler 26via a channel C provided from the pump housing 23 to the oil coolerhousing 28.

The control means 45 for controlling the speed of the pump 11 isprovided in thermal contact with the heat exchanger 27 in a manner suchthat the temperature of the control means 45 is stabilised by thecoolant flowing through the heat exchanger 27 of the oil cooler 26.

In both of the examples described, it will be appreciated that the oilcooler 26 and the control means 45 are located exteriorly of the sump Sin the air e.g. in a compartment of an engine housing, and this willenhance oil and control means 45 cooling. In the FIGS. 3 and 4arrangement, the pump housing 23 and the control means 45 housing areprovided with external fins F to promote heat exchange with the air,although these are not shown in the FIG. 4 drawing.

In both of the particular embodiments described, there is provided anoil cooler 26. However such oil cooler may not be essential in everyembodiment although the advantage of being able to stabilise thetemperate of a control means 45 positioned adjacent the pump 11 may belost. The advantage of providing the control means 45 so close to themotor 12 is so that leads between the two may be made as short aspossible, but in another arrangement where this advantage is notrequired, the control means 45 may be remotely positioned.

It will be appreciated from the above description and from the drawingsthat there may be provided a fluid pump, motor, fluid cooler and controlmeans as a modular unit with various housing walls being shared. Inanother arrangement at least one of the pump, motor, cooler and controlmeans may be provided by a separate unit which is attached to the otherunit or units.

If desired, a filter housing 32 may be provided integrally with the pumphousing, and/or with the oil cooler housing 28 so that the apparatus 10provides a self contained lubrication module which may be incorporatedinto an engine with a wide variety of different positions, without theconstraints imposed by an pump mechanically coupled to a driven part ofthe engine, or the filter position.

If desired the apparatus 10 as seen in and described with reference tothe drawings may incorporate a sieve filter to protect the pump 11particularly, from debris which may be contained within the engine oil,such filter being positioned in an inlet to the pump 11. In the figures,there will of course be an inlet to the pump via a housing of the pump,although this is not visible in all the figures.

Referring now to FIGS. 6 and 7 there is shown a yet another embodimentof the present invention, with similar parts to those described withreference to the previous figures indicated by the same referencenumerals.

In this embodiment, a pumping apparatus 10 includes an impeller 16 withis integrally provided with the motor 12.

The motor 12 is a brushless d.c. motor such as a switched reluctancemotor and includes stator windings 14 wound on radially inwardlyextending formations of an external stator core C, and an internal rotor15. The internal rotor 15 provides rotor salient poles which, as thestator windings 14 are energised, cause the rotor 15 to rotate in thestator core C. In this arrangement the rotor 15 is restrained axiallybetween two parts H1, H2 of a motor/pump housing 28 into which fluid tobe pumped may pass through an axial inlet 29 in one H1 of the housingparts, and be pumped from the housing through an axial outlet 30 of theother of the housing parts H2. Of course if desired, the inlet 29 and/oroutlet 30 may be provided other than axially, e.g. at radial positions,although as will be appreciated from what is described below, the fluidis pumped axially of the apparatus 10.

The internal rotor 15 has an internal opening 50 with generally inwardlyextending gear teeth like formations, six in this example, indicated at51. Within the internal opening 50 the impeller 16 is provided, theimpeller having generally radially outwardly extending gear-like teethformations 52, corresponding in number and configuration to the teeth 51of the rotor 15.

The impeller 16 may be mounted in the rotor 15 or may be free to rotateas indicated in the drawings, but in any event the impeller 16 rotatesabout an axis which is parallel to but spaced from an axis or rotationof the rotor 15. Thus at any time, only some the teeth 51, 52 are inengagement, and a pumping cavity is provided between the impeller 16 andthe internal rotor 15.

However, as the rotor 15 rotates, the impeller 16 will be rotated,albeit in a gerotor fashion within the rotor 15, and as a result, fluidwill be pumped with the fluid in contact not only with the impeller 16but with the rotor 15 (motive member) too.

The apparatus 10 is in use immersed in the lubricant to be pumped, andmay be connected with other components of an engine or the like, as withthe embodiments previously described and may conveniently be secured toor an integral part of an engine sumps. The apparatus 10 of FIGS. 6 and7 has advantage in that the overall axial length of the apparatus 10 maybe minimised as the impeller 16 is within the rotor 15, thus reducingweight and manufacturing costs too.

In each of the arrangements described above, it will be appreciated thatthe motor 12 is preferably a brushless motor such an a switchedreluctance motor, or a brushless direct current motor.

In each of the examples described, the pumping apparatus 10, or at leastthe pump 11 thereof is immersed in lubricant in an engine sump(s). Inanother example, the pump 11 may be immersed in lubricant in a separatelubricant reservoir, but in each case, lubricant from the sump or otherreservoir is in contact with the stator 14 and rotor 15 of the motormeans 12.

The features disclosed in the foregoing description or the followingclaims, or the accompanying drawings, expressed in their specific formsor in terms of a means for performing the disclosed function, or amethod or process for attaining the disclosed result, as appropriate,may, separately, or in any combination of such features, be utilised forrealising the invention in diverse forms thereof.

What is claimed is:
 1. An apparatus for pumping lubricant in an internalcombustion engine, the apparatus including a lubrication pump forpumping the lubricant, an electric motor for driving the pump, thelubricant being pumped from a reservoir in which at least thelubrication pump is immersed, and wherein the motor includes a statorand a rotatable motive member, the stator and rotatable motive member ofthe motor being in contact with lubricant from the reservoir wherein thepump and the motor are arranged with the pump and the motor immersed inthe fluid lubricant in the reservoir, the motor being devoid of ahousing or other outer casing.
 2. An apparatus according to claim 1wherein the reservoir for the lubricant is a sump of the engine.
 3. Anapparatus according to claim 1 wherein the motor is a brushless electricmotor, the stator having internal stator windings and an internal rotor,the internal rotor including an axially extending opening with generallyradially inwardly formations, and the pump includes an impeller which isreceived in the axially extending opening, the impeller having generallyradially outwardly extending formations which cooperate with theradially inwardly extending formations of the rotor so that the impelleris driven as the rotor rotates, the radially outwardly extendingformations of the impeller pumping the lubricant as the impeller isrotated.
 4. An apparatus according to claim 3 wherein the impellerrotates in the axially extending opening of the internal rotor about anaxis which is parallel to but spaced from an axis about which theinternal rotor rotates whereby in use, at any time, only some of thecooperating formations of the internal rotor and the impeller are incooperation, and a pumping cavity for lubricant to be pumped, isprovided between the internal rotor and the impeller.
 5. An apparatusfor pumping lubricant in an internal combustion engine, the apparatusincluding a lubrication pump for pumping the lubricant, an electricmotor for driving the pump, the lubricant being pumped from a reservoirin which at least the lubrication pump is immersed, and wherein themotor includes a stator and a rotatable motive member, the stator androtatable motive member of the motor being in contact with lubricantfrom the reservoir wherein the fluid is pumped by the pump through aheat exchanger where the lubricant is cooled by a coolant in thermalcontact therewith, the heat exchanger being located closely adjacent toa housing of the pump, in a position exteriorly of the reservoir.
 6. Anapparatus according to claim 5 wherein the pump only is immersed in thelubricant in the reservoir, the motor including a motor housing with oneor more passages for the lubricant from the pump to the interior of themotor housing.
 7. An apparatus according to claim 5 wherein thereservoir for the lubricant is a sump of the engine.
 8. An apparatusaccording to claim 5 wherein the motor is a brushless electric motor,the stator having internal stator windings and an internal rotor, theinternal rotor including an axially extending opening with generallyradially inwardly formations, and the pump includes an impeller which isreceived in the axially extending opening, the impeller having generallyradially outwardly extending formations which cooperate with theradially inwardly extending formations of the rotor so that the impelleris driven as the rotor rotates, the radially outwardly extendingformations of the impeller pumping the lubricant as the impeller isrotated.
 9. An apparatus according to claim 8 wherein the impellerrotates in the axially extending opening of the internal rotor about anaxis which is parallel to but spaced from an axis about which theinternal rotor rotates whereby in use, at any time, only some of thecooperating formations of the internal rotor and the impeller are incooperation, and a pumping cavity for lubricant to be pumped, isprovided between the internal rotor and the impeller.
 10. An apparatusfor pumping lubricant in an internal combustion engine, the apparatusincluding a lubrication pump for pumping the lubricant, an electricmotor for driving the pump, the lubricant being pumped from a reservoirin which at least the lubrication pump is immersed, and wherein themotor includes a stator and a rotatable motive member, the stator androtatable motive member of the motor being in contact with lubricantfrom the reservoir wherein there is provided a control means for theelectric motor, the control means being cooled in use by the coolant.11. An internal combustion engine having a sump for lubricant to bepumped, and an apparatus to pump the lubricant, the pumping apparatusincluding a lubrication pump for pumping the lubricant and an electricmotor for driving the pump, the lubricant being pumped from a reservoirin which at least the lubrication pump is immersed, and wherein themotor includes a stator and a rotatable motive member, the stator androtatable motive member of the motor being in contact with lubricantfrom the reservoir and including a management systems which interfaceswith a control means of the apparatus which is operative to controlmotor speed, the management system and control means controlling pumpspeed according to engine operating conditions.
 12. A method ofoperating an engine according to claim 11 wherein the method includesactuating the pumping apparatus prior to start-up of the engine and/orsubsequent to switching off the engine.
 13. A method of performing adiagnosis of engine malfunction including providing to an enginemanagement system, an input from a control means of an electric motor ofa pumping apparatus, the pumping apparatus including a lubrication pumpfor pumping the lubricant, and an electric motor for driving the pump,the lubricant being pumped from a reservoir in which at least thelubrication pump is immersed, and wherein the motor includes a statorand a rotatable motive member, the stator and rotatable motive member ofthe motor being in contact with lubricant from the reservoir.
 14. Alubrication module for an internal combustion engine, including apumping apparatus, the pumping apparatus including a lubrication pumpfor pumping the lubricant, and an electric motor for driving the pump,the lubricant being pumped from a reservoir in which at least thelubrication pump is immersed, and wherein the motor includes a statorand a rotatable motive member, the stator and rotatable motive member ofthe motor being in contact with lubricant from the reservoir and thelubrication module further including a lubricant cooler, the pumpingapparatus and the lubricant cooler being assembled together.